DOOR SHOCK ABSORBER

AMORTISSEUR DE CHOCS POUR PORTE

English Abstract

A door shock absorber is disclosed. The door shock absorber is to be typically used with dump bodies with doors that frequently enter into contact with the rear external structure of the dump body. The shock absorber comprises a spring and an actuator supporting the spring for absorption of any impact between the door and the rear dump body structure or any other type of base structure. The spring retractably traverses a casing between a deployed position and a retracted position. The actuator actuates the spring between the deployed position, the retracted position, and at least one intermediate position between the deployed position and the retracted position.

French Abstract

Un amortisseur de chocs pour porte est décrit. L'amortisseur de chocs pour porte doit généralement être utilisé avec des bennes basculantes dotées de portes qui entrent fréquemment en contact avec la structure externe arrière de la benne basculante. L'absorbeur de chocs comprend un ressort et un dispositif d'activation soutenant le ressort pour l'absorption de tout choc entre la porte et l'arrière de la structure de la benne basculante ou de tout autre type de structure de base. Le ressort traverse en se rétractant un boîtier entre une position déployée et une position rétractée. Le dispositif d'activation active le ressort entre la position déployée, la position rétractée, et au moins une position d'activation intermédiaire entre la position déployée et la position rétractée.

Claims

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CLAIMS
1. A door shock absorber for use between a base structure and a door,
comprising:
-a casing;
-a spring retractably traversing the casing between a deployed
position and a retracted position; and
-an actuator housed within the casing for actuation of the spring
between the deployed position, the retracted position, and at least
one intermediate position between the deployed position and the
retracted position,
wherein the spring absorbs an impact between the door and the structure
when the spring is placed in the deployed position.
2. The door shock absorber according to claim 1, wherein the actuator
is selected from the group consisting of a pneumatic balloon, a manual
mechanical actuator, an electromechanical actuator, an electro-static
actuator, a piezo-electric actuator, a thermo-mechanical actuator, an
electromagnetic actuator, and a polymer actuator.
3. The door shock absorber according to any one of claims 1 or 2,
wherein the spring is a rubber spring.
4. The door shock absorber according to any one of claims 1 to 3,
wherein the spring is a hollow rubber spring.
5. The door shock absorber according to any one of claims 1 to 4,
wherein the casing is fixed on the base structure, the actuator further
comprises an actuator support plate fixed on the casing, and the base
structure comprises an opening through which the spring passes.

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6. The door shock absorber according to any one of claims 1 to 4,
wherein the casing is fixed on the door, the actuator further comprises an
actuator support plate fixed on the casing, and the door comprises an
opening through which the spring passes.
7. The door shock absorber according to any one of claims 1 to 6,
further comprising a spring support plate connecting the spring to the
actuator.
8. The door shock absorber according to claim 5, further comprising a
spring support plate connecting the spring to the actuator and wherein the
opening of the base structure is sized to allow passage of the spring and to
block passage of the spring support plate.
9. The door shock absorber according to claim 6, further comprising a
spring support plate connecting the spring to the actuator and wherein the
opening of the door is sized to allow passage of the spring and to block
passage of the spring support plate.
10. The door shock absorber according to any one of claims 7 to 9,
further comprising a non-stick plate fixed on the casing and the spring
support plate is in slideable contact with a surface of the non-stick plate.
11. The door shock absorber according to claim 10, wherein the
surface of the non-stick plate is made of polytetrafluoroethylene.
12. The door shock absorber according to any one of claims 1 to 11,
further comprising a tube surrounding the spring and extending away from
the casing in a direction of travel of the spring.

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13. A dump body of a truck comprising a door shock absorber as
defined in any one of claims 1 to 12.

Description

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DOOR SHOCK ABSORBER
FIELD OF THE INVENTION
The present invention generally relates to a shock absorber for doors.
More particularly, the invention relates to a door shock absorber for doors
entering into contact with a base structure.
BACKGROUND OF THE INVENTION
Trucks having dump bodies, during the unloading process, produce large
banging sounds as material are being unloaded from the truck and the
truck moves in a jagged manner in order to shake out any materials from
the dump body. The weight of the door and the shaking movement of the
truck produce a very loud noise when the door enters into contact with the
structure of the dump body. In residential areas, this noise can become a
nuisance for the residents because its amplitude is significant and can
even surprise individuals who are not expecting such a sound even if they
are very far from the truck and the source of the banging noise. This has
led to a significant number of complaints from residents towards their
municipalities. In order to solve this noise problem, certain cities have
attempted to install on the rear of the dump bodies a piece of rubber that
could absorb a part of the energy of the closing door in order to decrease
the noise being generated. However, this solution is not entirely
satisfactory even though it might have reduced somewhat the number of
complaints from certain residents with regards to this noise.
JP 2001-010394 by Takeuchi discloses a door shock absorber system for
truck dump bodies. The system uses a piston mechanism to absorb the
shock of any contact between the dump body and the door as materials
are being unloaded from the truck. The piston mechanism occupies a
substantial amount space around the truck body.

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EP 1,305,539 by WILLNER describes a shock absorption system
comprising a plate supported by a magnet. The component that absorbs
the shock in this system can be placed in two different positions through
rotation of the component with respect to the magnet. This system does
not provide means for adjusting the component without having recourse to
a relative rotational movement.
US 6,039,388 by CHOI describes a shock absorption system between a
car hood and body. The system comprises an elastic element on the hood
and a second elastic element on the car body supported by a spring-
element. Any contact between the hood and the body is absorbed by the
contact between the two elastic elements and the spring-element. The
spring element can be mechanical, pneumatic or hydraulic. CHOI does not
describe means to put the elastic elements in a retracted position for
closing of the hood.
Therefore, there is presently a need for a new door shock absorption
system that improves the noise reduction associated with any banging of
the door against a dump body or any base structure, while providing a
retracted position for allowing proper closing of the door against the
structure.
SUMMARY OF THE INVENTION
An object of the present invention is to propose a door shock absorber that
is to be used on the interface between a door and a dump body structure
on a truck or any other base structure.
According to the present invention, there is provided a door shock absorber
for use between a base structure and a door, comprising:
-a casing;

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-a spring retractably traversing the casing between a deployed
position and a retracted position; and
-an actuator housed within the casing for actuation of the spring
between the deployed position, the retracted position, and at least
one intermediate position between the deployed position and the
retracted position,
wherein the spring absorbs an impact between the door and the structure
when the spring is placed in the deployed position.
As the door hits a dump body, for example, the door first hits the spring,
preferably a rubber spring, which is fixed on and positioned by the actuator,
which is preferably a pneumatic balloon. Consequently, the energy of the
closing door is absorbed by the rubber springs and the pneumatic balloons,
which has the effect of making the door bounce against the dump body
instead of making it collide directly on the steel structure. This decreases
significantly the noise associated with the contact between the door and
the dump body.
A non-restrictive description of a preferred embodiment of the invention will
now be given with reference to the appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a top view of the shock absorber in a rest position according to
a preferred embodiment of the present invention;
Figure 2 is a side cross sectional view of the shock absorber shown in
figure 1;

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Figure 3 is a top view of the shock absorber shown in work, absorbing a
contact between a door and a dump body structure in accordance with a
preferred embodiment of the present invention; and
Figure 4 is a side cross sectional view of the shock absorber shown in
figure 3.
DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION
Figures 1 to 4 illustrate a preferred embodiment of the invention. As shown
in Figures 1 to 4, the shock absorber according to the present invention
comprises a rubber spring and a pneumatic balloon supporting the rubber
spring.
More particularly, the present invention provides a door shock absorber for
use between a base structure 9 and a door 11. The door shock absorber
comprises a spring 5, preferably a rubber spring or a hollow rubber spring,
retractably traversing the base structure 9 between a deployed position
(shown in Figures 3 and 4) and a retracted position (shown in Figures 1
and 2). The shock absorber further comprises an actuator, preferably a
pneumatic balloon 7, for actuation of the rubber spring 5 between the
deployed position and the retracted position. The shock absorber also
comprises a casing 1 fixed on the base structure 9 and housing the rubber
spring 5 and the pneumatic balloon 7. As shown in Figures 3 and 4, the
rubber spring 5 absorbs an impact between the door 11 and the base
structure 9 when the rubber spring 5 is placed in the deployed position.
The actuator can selectively place the spring in a number of positions
between the retracted and deployed positions if required. In alternate
embodiments, the shock absorber may be placed on the door or any other
position to permit deployment of the spring between the door and the base
structure.

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Preferably, in dump body truck applications, the shock absorber is located
within a casing 1 fixed on the inside base structure 9 of the dump body. In
this configuration, the actuator further comprises an actuator support plate
fixed on the casing, and the base structure comprises an opening through
5 which the spring passes. Preferably, the shock absorber comprises a
spring support plate 4 connecting the spring to the actuator and the
opening of the base structure is sized to allow passage of the spring and to
block passage of the spring support plate 4. Hence, the interior structure of
the dump body plays the role of a stop structure for the support plate 4 of
an AeonTM rubber spring 5. Preferably, a non-stick plate 2 is fixed on the
casing and the spring support plate is in slideable contact with a surface of
the non-stick plate. Preferably, the surface of the non-stick plate is made of
polytetrafluoroethylene. As shown in Figures 1 and 2, to ensure good
sliding movement of the mechanism, a TeflonTM plate 2, for example, is
fixed into place with flat head screws 3. The casing 1 also places the role
of a support structure for the pneumatic balloon 7. The pneumatic balloon 7
support plate 6 is fixed on the casing 1 with a fastener, such as a bolt 8 in
order to allow the rubber spring 5 to traverse the rear structure of the dump
body. The shock absorber further comprises a round tube 10 having a
diameter slightly greater than the rubber spring 5 and acts as a guide for
movement of the spring 5 towards the back door panel 11 when it is being
deployed. In order to allow complete closing of the back door panel 11
against the base structure 9, and in order to insure proper sealing between
the door and the dump body structure, the rubber spring may be placed in
a retracted position as shown in Figures 1 and 2. In this retracted position,
the rubber spring does not touch the rear door panel, and therefore does
not interfere with any locking or retention system between the door and the
dump body.
As shown in figure 3, when the rear door panel locking or retention system
is unlocked, the pneumatic balloons 7 are inflated. The rubber spring 5

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support plate 4 slides on the TeflonTM plates 2. The pneumatic balloon then
rests against the internal base structure 9 of the dump body and therefore
pushes the rubber spring 5 beyond the round tube 10 in order to prevent
any contact between the rear door panel 11 against the structure of the
dump body base structure 9 as shown in figure 4. As direct contact
between the rear door panel and the dump body structure is avoided, there
is a significant reduction in the amount of decibels associated with the
noise due to banging of the door against the dump body structure.
This shock absorber system could easily be adapted to several other types
of doors that possibly hit against fixed structure, as long as some form of
actuation means is provided in order to move the spring between a
deployed and retracted position. The actuation means can be a pneumatic
balloon, a mechanical device actuated manually or any other type of similar
actuation mechanism. Preferably, the actuator is selected from the group
consisting of a pneumatic balloon, a manual mechanical actuator, an
electromechanical actuator, an electro-static actuator, a piezo-electric
actuator, a thermo-mechanical actuator, an electromagnetic actuator, and
a polymer actuator.
As mentioned above, in alternate embodiments, the shock absorber may
be placed either on the base structure, or the door or any other position to
permit deployment of the spring between the door and the base structure
for absorption of the contact between the door and the base structure.
Although the present invention has been explained hereinabove by a way
of a preferred embodiment thereof, it should be understood that the
invention is not limited to this precise embodiment and that various
changes and modifications may be effected therein without departing from
the scope or spirit of the invention.

Representative Drawing